The issue is the legally binding rights, privileges and obligations of consenting adult partners in households and families: Legal marriage, by that term or another. Resolving the issue requires little objective thought: Define the legal rights, privileges and obligations, and the Equal Protection Clause ensures they are universal.

I appreciate the Libertarian approach, but here it illustrates my usual problem with that approach in general: Abolishing government does not usher in utopian freedom, because government has many legitimate and vital duties. And yes, real injustices matter, especially when they compound bereavement with bankruptcy and/or separate families because the law does not consider one partner a "real" parent. We do not—cannot—ignore real injustice on the grounds it is only anecdotal; that is largely why the Fourteenth Amendment exists. What happened to the Ohioans who agreed so strongly they died for it?